Telephone-transmitter.



s. A. & R.- L. STIENBARGBR.

TELEPHONE TRANSMITTER.

APPLICATION FILED JULY 16, 1907.

Patented Jan. 12,- 1909.

.142 NORRIS Psrlns 99-. WAHINGTUN, D. c.

UNITED STATES PATENT OFFICE.

SHELDON A. STIENBARGER AND RALPH L. STIENBARGER, OF AUGUSTA, ILLINOIS.

TELEPHONE-TRANSMITTER.

T 0 all whom it may concern:

Be it known that we, SHELoox A. STIEN- BARGER and RALPH L. STIENBARGER, citizens of the United States, residing at Augusta, in the county of Hancock and State of Illinois, have invented certain new and useful Improvements in Telephone-Transmitters, of which the following is a specification.

Our invention relates to improvements in telephone transmitters in which it is sought to increase the carrying power of the transmitted current, and also to increase the volume of the sounds transmitted. lVe attain these objects by the mechanism illustrated in the accompanying drawings in which- Figure 1 is a side elevation of a telephone transmitter embodying our invention, the mouth piece, front plate and part of the frame of which is shown in cut section. Fig. 2 is similar to Fig. 1, except that it has the frame enlarged to carry duplicate transmission devices. Fig. 3 is a plan of the back electrode A, showing the multiple cells C C. Fig. 4, a side elevation of connecting bolt S, and Fig. 5, a plan of front electrode H showing the means for stiffening same.

Similar letters refer to similar parts throughout the several views.

Our invention consists in the novel construction and arrangement of parts as more fully hereinafter described and claimed.

\Ve make the auxiliary diaphragm, which is connected with the main diaphragm, so that it is entirely free to vibrate at all points, that is, being not fastened at the edges, so that the granular material in the multiplicity of cells is equally compressed, Whereas in those cases where the diaphragm is practically fast at its edges the central portion vibrates with greater amplitude, there by compressing the central portion of the granular material more than near the periphery.

The action of the secondary or auxiliary diaphragms of our invention is identical to the action of the auxiliary diaphragms of common transmitters except that the provision of multiple cells for carbon granules in our invention multiplies the power of the transmitter to carry or transmit current.

Referring to the drawings, the primary diaphragm is indicated at D and is connected to the secondary diaphragm H, by bolt S, so that any sound that vibrates D,

Specification of Letters Patent.

Application filed July 16, 1907.

Patented Jan. 12, 1909.

Serial No. 384,098.

will be transmitted to H by bolt S, in the manner common to other transmitters.

The secondary diaphragm H may be made of a single piece of any suitable conductor, but as it is very important that it should be as light as possible, we prefer to use a carbon disk C to which is secured a metallic disk H by soldering, electroplating or other suitable means; and as it is important that the disks H and C should be quite stiff, We secure this feature by brace ribs B B, secured to H, by soldering or other suitable means.

Frame piece F, is made wide to accommodate the ample front and back electrodes as shown, and when two pairs of electrodes are used it is twice as deep as shown by Fig. 2, and it is provided with cross piece T, to hold the front pair of electrodes by means of tubular bolt J through which passes bolt S, to which is secured the front one of the back pair of electrodes as shown.

A connecting wire t connects J and J with the back electrodes A, and A as shown; connecting wire t is connected to frame F.

The cell openings C. C. in f can be made through a single piece of felt or other suitable non conducting fabric which is secured to the back electrode by any suitable adhesive.

WVe wish it to be distinctly understood that we do not limit ourselves to any particular number of cell openings, nor to the details of construction as these may be changed without departing from the spirit of our invention.

Having described our invention, what we claim as new and wish to secure by Letters Patent is z- 1. In a telephone transmitter, a main diaphragm, an auxiliary diaphragm rigidly secured thereto, said auxiliary diaphragm being bodily movable and practically inflexible, a rear electrode carrying a multiplicity of cells, and granular material within said cells to be uniformly acted upon by said auxiliary diaphragm.

2. In a telephone transmitter, the combination of a main diaphragm, an auxiliary diaphragm rigidly secured thereto, said auxiliary diaphragm being free to vibrate as a whole, means for rendering such auxiliary diaphragm substantially inflexible, a rear electrode member carrying cells, and granular material within said cells and engaging said auxiliary diaphragm, substantially as with multiple cells for carbon granule, the

described. combination with the frame thereof of the V 3. In a telephone transmitter having an cross bar T, tubular adjustment bolt J? comauxiliary or secondary diaphragm combined bined substantially as shown and described 5 with multiple cells for carbon ranule, the and for the purpose specified.

combination therewith of sti ening ribs, SHELDON A. STIENBARGER. substantially as shown and described, and RALPH L. STIENBARGER.

for the purpose specified. Witnesses:

4.. In a telephone transmitter having an ANNA STIENBARGER,

10 auxiliary or secondary diaphragm combined MABEL STIENBARGER. 

